Electronic taximeter

ABSTRACT

An electronic taximeter with a simplified integrated circuitry having a sensor for computing distance travel charge, a constant frequency oscillator for computing waiting time charge, a counting means, control means in which the higher revenue charge takes precedence in being transmitted to the counting means, and an illuminated digital display for indicating the integrated time-distance charge in terms of monetary units.

United States Patent [191 Harwood [111 3,818,186 [451 June is, 1974 [5 ELECTRONIC TAXIMETER 3,512,706 5/1970 Bruce-Sanders 235/30 R [75] Inv to Ma H. arw od, ing ton, NJ. 3,703,985 11/1972 Berg 235/30 R [73] Assignee: Machining Methods Industries, East Pn'mary ExaminerRichard B. Wilkinson Rutherford, NJ. Assistant Examiner-Vit W. Miska [22] Filed Nov 3 1972 Attorney, Agent, or Firm-Leo C. Krazinski [21] Appl. No.: 303,467 57 ABSTRACT An electronic taximeter with a simplified integrated [52] US. Cl. 235/30 R, 235/45 R circuitry having a sensor for computing distance travel [51] Int. Cl. G07b 13/10 charge, a constant frequency oscillator for computing [58] Field of Search 235/30, 33, 45, 103, 103.5, waiting time charge, a counting means, control means 235/ 104; 328/45 in which the higher revenue charge takes precedence in being transmitted to the counting means, and an il- [56] References Cited luminated digital display for indicating the integrated UNITED STATES PATENTS time-distance charge in terms of monetary units. 3,388,859 6/1968 Kelch et al 235/30 R 9 Claims, 9 Drawing Figures 12 ROOF SP5 LIG HTS 2222 SCHMITTS 5V To ALL 5 T *rmcaen- $553132; w/Cj/ 'ro 14 E F9 rem VOLTAGE 12 v swlTcH REGULATOR UNREGULRTEDi c l iz l ioe TRIP COUNTER $522 5 6? MODE JG EB INDICATOR 42f FARE unn- REQETSS IOTALlZER COUNTER TIME FLHG DROP REFFERENCE FIRST DISPLAY 5 men-m. /2f

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1 ELECTRONIC TAXIMETER BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electronic taximeter that reduces the number of parts of said prior patented electronic meter and yet accomplishes the necessary result in a more accu- Another object is to provide an improved electronic taximeter wherein a rate change is accomplished by changing bias on data inputs without adding components.

A further object is to provide an improved electronic taximeter of maximum accuracy having encapsulated tamper proof circuitry.

Other and further objects will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

In accordance with the present invention, the foregoing objects are generally accomplished by providing an improved electronic taximeter which comprises five essential elements, namely, 1) time and distance scalers and pulse shapers, (2) time and distance discriminator, (3) time and distance counter and integrator, (4) associated programming devices, and (5) digital display.

Except for trips, total miles, paid miles, unit counters, and manual switches, the meter herein employs integrated circuitry thereby eliminating entirely the service problem. The circuitchips used in this improved meter are readily substituted and do not require any amount of maintenance.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:

FIG. 1 is a block diagram of an electronic taximeter embodying the present invention.

FIG. 2 is a sectional view of a speedometer pickup device.

FIG. 3 is a schematic view of the electronic apparatus shown in FIG. 2.

FIG. 4 is a block diagram of the discriminator shown in FIG. 1.

FIG. 5 is a schematic block view of the time reference block shownin FIG. 1.

FIG. 6 is a block diagram of the display calculator shown in FIG. 1.

FIG. 7 is a block diagram of the fare totalizer shown in FIG. 1.

FIG. 8 is a block diagram of the digital display shown in FIG. 1.

FIG. 9 is a front elevational view of an electro digital panel for the electronic taximeter. v

A general description will now be given of each of the five essential elements of the electronic taximeter, indicated hereinbefore.

1. TIME AND DISTANCE SCALERS & PULSE SHAPERS All taximeters operate basically on the same principle. They collect information provided by a mechanical clock for time measurement and mechanical connection to drive, that is, gear box or speedometer cable, for distance measurement. Two rates are set which assure the taxi owner to collect his minimum revenue, that is, (a) rate/hr and (b) rate/mile. If the vehicle is moving slowly the hourly rate dominates. However, as soon as a certain speed is reached, the meter changes over to the distance rate which provides a higher revenue. It is evident therefore that both the time sealer and distance scaler must be extremely accurate. The time base in this meter is an electronic clock which is adjustable to provide the exact number of pulses per second corresponding to the hourly rate. In order to assure accuracy the circuitry used in this invention employs a square wave generator compensated for changes in temperature or other environmental conditions. This clock is used not only for time base but for all other comparative measurements.

The distance scaler used in this invention is coupled to the output of the speedometer connection (mechanical or electronic) providing a fixed number of square wave-pulses per mile, thus providing extremely accurate distance measurements. Both the clock and distance scalers are fully programable to provide corrections, such as needed for tire wear, distance rate changes or hourly rate changes.

Since both sources of square waves are the only information producing devices, it is very important that the pulse shape produced by both of them be of very accurate duration and very precise shape. In order to assure both of these features the produced signals are fed into a pulse shaping device, termed a Schmitts trigger, which has a very accurate output regardless of the input fed into it. Thus until this point we have obtained two precise measurements, time and distance.

2. TIME DISTANCE DISCRIMINATOR As mentioned hereinbefore, the rate which provides higher revenue must be the dominant rate, for a slow moving or standing vehicle would provide no revenue.

In such case the hourly rate takes over assuring the which revenue is the same provided either by'distance or time rate. This speed is obtained by dividing hourly rateby distance rate, i.e. $5.00 per hourly rate and cents per 1/5 mile rate would produce a critical speed of 10 MPH.

To assure accuracy and to provide a minimum time delay during changeover a special time-distance discriminator is connected to both outputs from the pulse shaper. This invention operates on first come first get basis. It employs two BCD counters in a symmetrical arrangement, cross coupled in such a way that only one output at a given time is possible. One counter is connected to the output from the time reference pulse shaper, while the other counter is connected to the dis,- tance scaler pulse shaper.

The time reference signalis present continuously as long as the taximeter is in On position and power is supplied to the circuitry, regardless whether or not the taxi is moving or standing.

The BCD counter connected to the time reference pulse shaper will count the pulses from the clock, produce an output at the end of the count, and by proper arrangement this output is used to clear the BCD counters, as well as to set the flip-flop gate combination to pass the clock pulses through to the next stage.

The automatic and simultaneous clearing of both BCD counters to zero is the basic principle of operation of the discriminator. As each time both BCD counters are cleared, they start to count from the beginning and, as soon as one reaches its final count, both BCD counters are reset to zero and the signal corresponding to the BCD counter which reached its final count first will be passed to the next stage.

Assume that the taxi is beginning to move and signal pulses are beginning to show at both BCD counters.

Since the automatic clearing of both counters is simultarieous, onlyone of them willhave an output which will pass the proper signal to the next stage. As long as the taxi is moving with speed below the critical speed the speedometer signals will not go through, since the time reference will produce an output first and therefore clear both BCD counters without giving the BCD counter connected to the speedometer a chance to reach a final count. As soon as the taxis speed increases and exceeds the critical speed, the BCD counter connected to the speedometer will produce an the taxi drops below critical speed in which case the time reference will take precedence, block the speedometer signals from going and let the time (clock) reference signal to the nex stage.

3. TIME DISTANCE COUNTER, lNTEGRATOR This invention provides a means of counting and integrating signals supplied by the time distance discriminator in a way requiring no additional counting aids. In most counters having a few digits a number of gates and inverters must be used to obtain a final count. In a BCD (Binary Counting Decade) system counting four digits, a minimum of four and maximum of sixteen outputs must be fed into gates to provide a decimal output, thus counting from 1 to 1,000 would require four gates, each having four inputs. This invention provides a final count with only one single output, thus counting always For example, if a count of 200 were required, it

would necessitate the use of 3 BCD counters and three gates connected, one to eachcounter. The same count of 200 in this invention is obtained by setting the final countto be 1,000 with one single output from the last counting decade, and presetting the counter to 800 which results in the total counting of 200. Presetting is done automatically by feeding the output pulse to the preset terminal of the individual counters. Since the entire resetting cycle is done during only one signal pulse, no time or count is lost. Mathematically it can be represented 200 1,000-800 or final count setting less preset value. It can .be seen from this derivation how easily any number of counts may be obtained without use of additional components. This counter integrates pulses obtained from either time or distance scalers and provides an output after reaching its final count. This output is then used to activate the digital display showing the total in terms of monetary units. Each cycle is repeated at a predetermined rate set bythe hourly and distance rates.

4. PROGRAMING DEVICES Programing devices used in this invention consist of several electronic switches designed in such a manner that no change in wiring is needed to change rates or fare. It is only a matter of grounding or not grounding data inputconnections in such a way as to preset and- /or' reset BCD counters in proper sequence to obtain desired counting order, as dictated by the local rates, and as mentioned previously, no additional 'components or change of components is needed.-

5. DIGITAL DISPLAY Digital display used in this invention consists of several illuminated displays which show the integrated time-distance interms'of monetary units. In-o rder to display the proper amount a counter is connected to each display'and programmed to correspond to change in accordance with the monetary system used. In case of the decimal system each display shows numerals from 0 to 9.

Since the segments of each display are illuminated, they are clearly visible regardless of the light ambient. Changes in fare are accomplished in the same way as i were changes in rates. Only data inputs to the BCD counters have to be properly grounded or disconnected from ground to obtain the desired count. Since this display has no moving mechanical parts, the change is completely noiseless and instantaneous.

Referring now to the drawings-in detail, a switch 10 (FIG. 1) is permanently shown connected to a nominal 12 volt battery, which varies from 8 to 16 volts DC. Power to the taximeter is connected by the switch 10 which is shown also located on a panel 11 (FIG. 9) of the taximeter. In the normally OFF position the switch 10 energizes roof lights 12 and one light in a mode indi cator 13 to provide a visual display from the outside, such as FOR HIRE, NOT FOR H1RE, or OFF DUTY: but no energy is supplied to a voltage regulator 14 or speedometer sensor 16. i

During operation of the switch from OFF to ON position all circuitry is provided with positive voltage from the voltage regulator 14 and at the same time information is fed to all circuitry to preset itself to predetermined mode according to local rates and so instructed by properly biased data inputs (FIG. 6), as well as setting the first drop (flag) to display the proper amount (FIG. 7). At the same time the roof lights 12 are extinguished and one count is added to an electromechanical trip counter 17. In addition while the vehicle is stationary, the following elements (FIG. 1) were activated, namely, time reference 18, discriminator 19, and digital display 21.

As soon as the vehicle begins to move, the speedometer sensor 16 receives information. As to the sensor details, see FIG. 2, it comprises a housing 22 having at one end a male connector 23 for connection to a speedometer cable (not shown), at its other end a female connector 24 for connection to a speedometer (not shown), and a shaft 26 rotatably carried upon antifriction bearings 27 within the housing for interconnecting the connectors 23, 24. Preferably, the connectors 23, 24 are affixed to the shaft 26 and are rotatable therewith. About the center of the housing is shown an opening 28, which is adapted to register with an opening 29 in the shaft 26; while opposed, enlarged openings 31, 32 in extension of housing opening 28 are provided for a light emitting diode 33 and photo sensitive transistor 34, respectively, as also shown schematically in FIG. 3. Consequently, during movement of the vehicle and rotation of the speedometer shaft 26 the rotating shaft opening 29 opens and closes with intermittent transmission of light from the light emitting diode 33 to the photo sensitive transistor 34. The output from the transistor 34 is proportional to the amount of interrupted light received, thereby providing a relative measurement of distance travelled in unit time.

The advantages of this system are:

1. Light emitting diode 33 has no filament and does not produce heat as do other light sources.

2. Unless power source fails the diode 33 is tamper proof (unlike magnetic or mechanical devices).

3. Having no hot filament is vibration and temperature proof.

4. Phototransistor 34 output does not require any conversion to electronic systems, since its output can be connected directly to an amplifier, thereby eliminating the need of transducers.

5. The rise and fall time of both diode 33 and transistor 34 are so short that no additional components are needed to eliminate persistence or memory, such as are exhibited by magnetic or resistive devices.

6. Magnetic, mechanical or resistive devices can be easily defeated by introducing an externally strong magnetic field, mechanical friction etc.

From the moment the switch 10 is rotated to the ON position and voltage is supplied to the time reference 18 a voltage controlled oscillator 36 (FIG. 5) starts to oscillate at a rate preset to correspond to the time interval required by local rates.

Since the voltage supply is regulated by the regulator 14 and does not vary by more than 1 percent including temperature variations, the time reference circuit 18 once set by means of a voltage divider 37 (FIG. 5) and capacitor 38 will remain within this accuracy during the entire operating cycle. A gated input 39 and output 41 (FIG. 5) provide a means to enable or disable the time reference 18 or change its interval as may be required in a dual tariff operational mode.

ELE OF A TYPICAL OPERATIONAL CYCLE 1. Assuming the following local rates are:

A. Flag drop 60 cents/ first one-fifth mile B. 10 cent each additional one-fifth mile C. $5.00] hour waiting time 2. The taximeter must be adjusted to do the followmg:

A. Display 60C for the first drop by properly biasing data inputs on fare totalizer 42 (FIG. 7) to display .60 as soon as the switch is put in ON position. This is accomplished by presetting Tens of Dollars, Dollars, and Cents circuits 43, 44 & 46, respectively, to 0 while dimes circuit 47 (Fig. 7) is preset to 6. As soon as switch 10 (FIG. 9) is rotated from OFF to ON position the flag preset load line is grounded momentarily, therefore displaying .60.

B. Time reference 18 must be preset to add 10 cents to the fare for each 72 seconds of waiting time, which is accomplished by adjusting voltage bias 37 of the time reference 18 (FIG. 5), for 72 seconds.

C. Display calculator 49 must add 10c for each additional one-fifth mile, which is accomplished by properly biasing data inputs of BCD counters 51, 52, 53 & 54 (FIG. 6). The reset load line will receive a count signal at the completion of each one-fifth mile, or 72 seconds, of waiting time or any composite integrated distance and time.

l-laving set the taximeter for the specified rates, it is now operational and the normal cycle would be as follows:

As soon as the passenger enters the taxi and gives his destination, the driver turns the selector switch 10 to ON position. This disables the roof lights 12, enables the mode indicator 13, the voltage regulator 14, displays first drop (flag) .60 and enables all the remaining circuitry. While the vehicle is still standing or moving slowly only, that is, less than 10 miles per hour, in this example, the time reference 18 signals reach the display calculator 49, as the discriminator 19 did not let the speedometer distance rate pass through. The system remains in this state as long as the time reference 18 provides a higher revenue. Having reached and/or exceeded 10 MPH, the system will drop the time rate by cutting out the time reference 18 and cutting in the distance reference.

The 10 MPH is the speed at which the revenue is identical for both time or distance modes for the set of conditions mentioned previously. The change over is done by the discriminator 19 (FIG. 1) in the following fashion.

Both the speedometer distance sensor 16 and the time reference 18 outputs enter the discriminator 19 through Schmitts triggers 56 and 57, respectively, in order to provide data of equal amplitude and shape. The function of the discriminator 19 is to provide one output only corresponding to the higher revenue. Therefore it is a selective rate sealer designed to operate per unit time dictated by the higher revenue set by the conditions. Since the conditions do not vary for one locality, the speed at which the revenue becomes greater is fixed and the discrimination is automatic once all data inputs are set for the entire system.

Referring to FIG. 4, information to the discriminator .19 enters from both Schmit'ts triggers 56' and 57 into the time reference BCD counter 59 and into the speedometer BCD counter 58, respectively. Both the time reference signals and speedometer signals are always present at the inputs to the BCD counters 58 and 59 as well as at one of the inputs to gates 63 and 64 forming signal line A for the time reference and signal line B for speedometer sensor. Because of the symmetrical arrangement only one of the gates 63 or 64 can be opened to pass a signal through depending on the state of flip-flop'61... The state of the flip-flop 62 is determined by the conditions of gates 60 and 61 which are in turn dependent on the state of the BCD counters 58 and 59. Gates 60 and 61 are also cross coupled with the Clear inputs of the opposing BCD counters 59 and 58 providing a means of simultaneous count start.

Signal line A has a pulse train present on it as soon as the taxi meter is turned On and is in waiting time mode. As long as the vehicle is not moving, signal line B has no pulse available and the following condition will exist. The BCD counter 59 will count to nine (9) at which time it will produce an output into gate 61 and it will reset to zero automatically. Gate 61 will clear BCD counter 58 (at this time there is no count in it) and at the same time Gate 61 will put flip-flop 62 into a state permitting gate 64 to pass signals present on sig nal line A and also close gate 63. Of course, at this time this is the only revenue producing mode, since the vehicle is stationary. As soon as the vehicle starts to move, pulses are now present on both signal lines A and B. As long as the vehicle is moving with speed below, say 10 MPH, the number of pulses per unit time is lower than the number of pulses provided by the time reference and, since both BCD counters 58 and 59 start counting simultaneously, it is obvious that BCD counter 59 will reach the count of 9 prior to BCD counter 58, reset both itself and BCD counter 58 to zero and through gate 61, flip-flop 62 and gate 64 pass the time pulses present on signalline A through to the display calculator 49. As stated before, since gate 64 is open the state of flip-flop 62 closes gate 63. As the speed of the vehicle increases, the number of pulses per unit time also increases more and more until it is equal and then exceeds the number of pulses from the time reference.

Since both BCD counters 58 and 59 start to count simultaneously, at this time BCD counter 58 reached the count of nine first and therefore provided an output into gate 60, reset itself to zero andat the same time cleared counter 59 to zero. Gate 60 has now inverted the state of the flip-flop 62 which has now opened gate 63 passing the pulses present on signal line B through to the display calculator 49 and, closing gate 64, it has blocked pulses present on signal line A from going through.

This condition will now prevail as long as the vehicle is moving with a speed higher than the critical speed in this case, namely, 10 MPH. This will of course provide a higher revenue, since more pulses were present on signal line B than on signal line A and this is the line open into the display calculator 49.

As soon as the vehicle slows down and its speed falls below 10 MPH, the situation reverses itself back to the original state, so that BCD counter 59 has an output into gate 61 which reverses the position of the flip-flop 62 thusly opening gate 64 and letting pulses present on signal line A through, which became again the higher revenue producing when entered into display calculator 49. v I

I This continuous discrimination of lower count pulses goes on for every 10 pulses provided by either signal line A or B, whichever line provides higher revenue. In cases where the time reference is not needed,flip-flop 62 is fixed in one position by the external switch (10) in waiting time off mode. In this state gate 64 closes the passage of pulses present on signal line A and gate 63 opens passing through pulses present on signal line B regardless of their repetitive rate. The output from the discriminator 19 for each integrated time distance input is transformed into one output corresponding to 72 seconds, one-fifth mile or any combination of parts of each. s

At the end of each cycle, the output available from the display calculator 49 corresponding to one 10 cent drop is fed into the fare totalizer 42, unit counter 65 and nand gate 66 (FIG. 6), into reset load line of the display calculator 49, and the fare totalizer 42, until the trip is completed. The fare totalizer 42 was preset to advanceby 10 cents for each output from display calculator 49 by having proper bias at the data inputs.

- Each BCD counter 43, 44, 47 and 46 (FIG. 7) has four outputs which are fed into the digital display 21, its decoder drivers 68, 69, 70 and 71 (FIG. 8) and converted into seven segmental digital displays 72, 73, 74 and 75, showing the total fare on four illuminated displays 76 (FIG. 9).

Having reached his destination, the driver will turn the switch 10 into TIME OFF position in order to deenergize the time reference 18. Now there is no signal available from either speedometer sensor 16.or time reference 18 and therefore the digital display 21 will remain in its position corresponding to the last l0 cent addition.

After discharging the passenger the driver will turn the switch 10 to the OFF position. During the transition from TIME OFF to OFF position, he will de-energize all circuitry and add onecount to the trip counter 17. At the same time the mode indicator lights 13 will be extinguished and the roof lights 12 energized.

The taxi is now ready to receive its next passenger.

From the foregoing description it will be seen that the present invention provides an improved electronic taximeter having substantially no time loss during change over from a time scaler to a distance scaler or vice versa, thereby providing maximum accuracy, the rate change being readily accomplished by a bias change on data inputs without adding components.

As various changes may be made in the circuitry, form, construction and arrangement of parts herein, without departing from the spirit qnd scope of the invention and without sacrificing any of its advantages, it is to be understood that all matters are to be interpreted as illustrative and-not in any limiting sense.

What is claimed is:

1. An electronic taximeter'in a vehicle for determin ing a passenger fare and displaying the same on an illuminated digital display panel comprising, in combination, a time scaler, including an electric clock for generating pulses in response to time travelled and or time shape, a discriminator for receiving said time and distance pulses from said pulse shaper including a counter for each of said time and distance pulses, means in said discriminator for accepting one of said pulses and rejecting the other of said pulses, the pulses of the highest repetitive rate being accepted, a display calculator responsive to output of said discriminator in which a proper count is obtained by setting a final count and presetting a number into the display calculator, whereby the difference between the final count and presetting number is the desired count, a fare totalizer for integrating each output pulse from said display calculator after a final count has been reached, and an illuminated digital display responsive to said fare totalizer counter for indicating in monetary units the passenger fare.

2. An electronic taximeter in accordance with claim 1, wherein said speedometer includes a housing, a shaft in said housing coaxial with and rotatable by a taxi speedometer cable, a light emitting diode, and a photo sensitive transistor responsive to said diode, wherein said housing has an opening and said shaft also has an opening for intermittent registration with said housing opening, whereby light pulses emitted by said diode and passing through said openings actuate said transistor.

3. An electronic taximeter in accordance with claim 1, wherein said discriminator means includes two counters, one counter for distance pulses and the other counter for time pulses, a flip-flop and gate forpassing through only the highest repetitive rate pulses.

4. An electronic taximeter in accordance with claim 2, wherein said diode and said transistor are carried by said housing.

5. An electronic taximeter in accordance with claim 3, wherein said counters are BCD counters.

6. An electronic taximeter in accordance with claim 5, wherein said BCD counter for said time pulses assumes control when said vehicle travels at less than a predetermined critical speed.

7. An electronic taxirneter in accordance with claim 6, wherein said BCD counter for said distance pulses assumes control when said vehicle travels at more than a predetermined critical speed.

8. An electronic taximeter in accordance with claim 7, including a plurality of electronic switches for programming fares in the taximeter, whereby changes in the fares are made simply by grounding or ungrounding data input connections in said display calculator and fare totalizer.

9. An electronic taximeter in accordance with claim 9, wherein each of said switches is a circuit chip containing a plurality of flip-flops or gates. 

1. An electronic taximeter in a vehicle for determining a passenger fare and displaying the same on an illuminated digital display panel comprising, in combination, a time scaler, including an electric clock for generating pulses in response to time travelled and or time standing, a distance scaler including a speedometer for generating pulses in response to distance travelled, a pulse shaper responsive to pulses from said time and distance scalers for emitting pulses of predetermined shape, a discriminator for receiving said time and distance pulses from said pulse shaper including a counter for each of said time and distance pulses, means in said discriminator for accepting one of said pulses and rejecting the other of said pulses, the pulses of the highest repetitive rate being accepted, a display calculator responsive to output of said discriminator in which a proper count is obtained by setting a final count and presetting a number into the display calculator, whereby the difference between the final count and presetting number is the desired count, a fare totalizer for integrating each output pulse from said display calculator after a final count has been reached, and an illuminated digital display responsive to said fare totalizer counter for indicating in monetary units the passenger fare.
 2. An electronic taximeter in accordance with claim 1, wherein said speedometer includes a housing, a shaft in said housing coaxial with and rotatable by a taxi speedometer cable, a light emitting diode, and a photo sensitive transistor responsive to said diode, wherein said housing has an opening and said shaft also has an opening for intermittent registration with said housing opening, whereby light pulses emitted by said diode and passing through said openings actuate said transistor.
 3. An electronic taximeter in accordance with claim 1, wherein said discriminator means includes two counters, one counter for distance pulses and the other counter for time pulses, a flip-flop and gate for passing through only the highest repetitive rate pulses.
 4. An electronic taximeter in accordance with claim 2, wherein said diode and said transistor are carried by said housing.
 5. An electronic taximeter in accordance with claim 3, wherein said counters are BCD counters.
 6. An electronic taximeter in accordance with claim 5, wherein said BCD counter for said time pulses assumes control when said vehicle travels at less than a predetermined critical speed.
 7. An electronic taximeter in accordance with claim 6, wherein said BCD counter for said distance pulses assumes control when said vehicle travels at more than a predetermined critical speed.
 8. An electronic taximeter in accordance with claim 7, including a plurality of electronic switches for programming fares in the taximeter, whereby changes in the fares are made simply by grounding or ungrounding data input connections in said display calculator and fare totalizer.
 9. An electronic taximeter in accordance with claim 9, wherein each of said switches is a circuit chip containing a plurality of flip-flops or gates. 